INVESTIGATION OF ANOMALIES IN THE ELECTRONIC DISPERSION OF THE HUBBARD MODEL, t–J AND t–J* MODELS WITHIN THE CLUSTER PERTURBATION THEORY IN THE X-OPERATOR REPRESENTATION

The electronic structure with the spectral line broadening corresponding to the angle-resolved photoemission spectroscopy resolution has been calculated for the Hubbard model, t–J and t–J* models within the norm-conserving cluster perturbation theory. The electronic dispersion anomalies similar to the high-energy kinks observed in the angle-resolved photoemission spectroscopy experiments are obtained at the energy scale of order of the hopping integral t. The doping dependence of the high-energy anomalies for different Coulomb repulsion values is discussed. The influence of the threesite correlated hopping on the results is analyzed.

Keywords:
high-temperature superconductivity, electronic structure of cuprates, high-energy kinks, cluster perturbation theory, the Hubbard model, t–J-model
УДК 538.94

INVESTIGATION OF ANOMALIES IN THE ELECTRONIC DISPERSION OF THE HUBBARD MODEL,t–J AND t–J* MODELS WITHIN THE CLUSTER PERTURBATION THEORY IN THE X-OPERATOR REPRESENTATION